Mr.checker Wikipedia Commons. Louise Docker from sydney, Australia, Wikimedia Commons. Angelique Paulk

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1 Mr.checker Wikipedia Commons Louise Docker from sydney, Australia, Wikimedia Commons Angelique Paulk

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3 Objectives How does learning and memory operate at the behavioral level? How can you train an insect? What are the different types of memory? André Karwath aka Aka Wikipedia Common

4 Learning, memory, and everything else insects do! Learning and memory enables insects to adapt to their environment, their situations, and to become one of the most successful groups on the planet. To study learning and memory, researchers have focused on two main model species: 1. The vinegar fly Drosophila melanogaster 2. The honeybee Apis mellifera André Karwath aka Aka Wikimedia Common Louise Docker from sydney, Australia, Wikimedia Common

5 The vinegar fly Drosophila melanogaster: a model for understanding the role of genetics in learning and memory Drosophila melanogaster has been essential for understanding the function of synapses, of neurons, and various aspects of the nervous system The genetic toolkit available for studying the genetic mechanisms underlying behaviour has allowed researchers to dissect neural circuits while looking at animal behaviour The learning and memory assay: the Tully paradigm to train large groups of flies to associate an odour with electrical foot shock Mr.checker Wikipedia Commons

6 Learning and memory: How to train a fly The study of learning and memory have been addressed in Drosophila using the olfactory shock treatment Using this population approach, numerous learning and memory mutants have been found. Odour 2 André Karwath aka Aka Wikimedia Commons Odour 1 Odour 1 1. Place the flies in a chamber with an odour (odour 1) in the presence of electrified shock from the chamber 2. Let the flies enter two chambers to see if they learned to avoid the odour associated with electric shock

7 Learning and memory: How to train a fly André Karwath aka Aka Wikimedia Commons Another setup involves tethering the fly to a post and using a torquemeter to detect when the fly tries to turn left or right, called the tethered flight arena setup Check out movies of this online: The fly can be trained to avoid looking at one object when the object is associated with heat Heat No heat Avoidance No avoidance Liu G, Seiler H, Wen A, Zars T, Ito K, Wolf R, Heisenberg M, Liu L (2006) Distinct memory traces for two visual features in the Drosophila brain. Nature. 439:

8 The honeybee Apis mellifera: a model for understanding learning and memory Honeybees have long been used and domesticated by humans for pollination. They forage from a central site, have to navigate a terrain, and learn optimal foraging approaches. They can be trained to learn colours, patterns, motion cues, etc. R J Higginson Wikimedia Commons Ken Thomas Wikimedia Commons

9 The honeybee Apis mellifera: a model for understanding learning and memory R J Higginson Wikimedia Commons Ken Thomas Wikimedia Commons Karl von Frisch, the researcher who discovered the honeybee waggle dance, also found honeybees can detect colour by training them to coloured objects. von Frisch K (1914) Der Farbensinn und Formensinn der Biene. Jb Abt Allg Zool Physiol 37: von Frisch K (1965) The Dance Language and Orientation of Bees. Cambridge: Belknap Witthöft W (1967) Absolute Anzahl und Verteilung der Zellen im Hirn der Honigbiene. Z Morph Tiere 61:

10 The honeybee Apis mellifera: a model for understanding learning and memory Honeybees can be trained to learn colours, patterns, motion cues, etc. Numerous researchers have found that honeybees can perform complex behavioural tasks: Dyer AG, Chittka L (2004). Fine colour discrimination requires differential conditioning in bumblebees. Naturwissenschaften 91: Dyer AG, Rosa MGP, Reser DH (2008) Honeybees can recognise images of complex natural scenes for use as potential landmarks. J Exp Biol 211: Giger A, Srinivasan MV (1996) Pattern recognition in honeybees: chromatic properties of orientation analysis. J Comp Physiol A 178: Giger AD, Srinivasan MV (1995). Pattern recognition in honeybees: eidetic imagery and orientation discrimination. J Comp Physiol A 176: Giurfa M (2007) Behavioral and neural analysis of associative learning in the honeybee: a taste from the magic well. J Comp Physiol A 193: Giurfa M, Eichmann B, Menzel R (1996) Symmetry perception in an insect. Nature 382: Giurfa M, Zhang SW, Jennett A, Menzel R, Srinivasan MV (2001) The concepts of sameness and difference in an insect. Nature 410: Lehrer M, Srinivasan MV, Zhang SW, Horridge GA (1988) Motion cues provide the bee s visual world with a third dimension. Nature 332: Srinivasan MV (1993) Pattern recognition in the honeybee: recent progress. J Insect Physiol 40: Srinivasan MV, Lehrer M (1988) Spatial acuity of honeybee vision and its spectral properties. J Comp Physiol A 162: Srinivasan MV, Zhang SW (1998) Probing perception in a miniature brain: Pattern recognition and maze navigation in honeybees. Zoology 101: Srinivasan MV, Zhang S, Altwein M, Tautz J (2000). Honeybee navigation: nature and calibration of the odometer. Science 287: Srinivasan MV, Zhang SW, Bidwell NJ (1997). Visually mediated odometry in honeybees. J Exp Biol 200: Zhang SW, Bartsch K, Srinivasan MV (1996). Maze learning by honeybees. Neurobiol Learn Mem 66: Zhang SW, Lehrer M, Srinivasan MV (1999) Honeybee memory: navigation by associative grouping and recall of visual stimuli. Neurobiol Learn Mem 72:

11 Learning and memory: How to train a bee Before training, the odour reward does not elicit a response The honeybees can be trained to go to a specific area or visual cue by associating it with a sugar reward. In honeybees (and bumblebees) can be trained to extend their proboscis with the application of sugar to the antenna, which is called the proboscis extension reflex (PER). In this case, the sugar reward can be associated with an olfactory or visual cue. Touching sugar to the antenna triggers proboscis extension By adding the odour stimulus before the sugar reward, the bee can associate the odour with the sugar. Presenting the reward alone triggers proboscis extension

12 Learning and memory: Different types of memory Learning and memory can involve three main phases: 1. Acquisition: the formation of the memory, such as associating a stimulus with a sugar reward or an aversive shock (training) 2. Consolidation: neural changes occur to allow for the stabilization of the memory, which happens for the period after training 3. Retrieval: the process of remembering the association or the memory, which is tested after training

13 Heisenberg M (1998) What do the mushroom bodies Heisenberg M (1998) What do the mushroom bodies do for the insect brain? Learn Mem 5:1 10. the insect brain? Mem 5:1-10. Heisenberg M (2003) Mushroom body memoir: Heisenberg M (2003) Mushroom body memoir: from maps to models. Nat Rev Neurosci 4: maps models. Neurosci 4: Learning and memory: Different types of memory Memory can be divided into short term (STM), middle term (MTM), and long term (LTM) memory. The different types of memory have different time courses: Retention STM MTM ARM LTM minutes 1 hour Greater than 24 hours In Drosophila, a fourth type of middle term memory was discovered which is anaesthesiaresistant memory (ARM). While other mid term memory can be blocked with placing the flies on ice a certain period of time after training, ARM survives the procedure.

14 Learning and memory: types of training Insects, and, really, any animal, can be trained to learn in several ways. These different training regimes can trigger different short and long term memory pathways. Massed training Spaced training Training sessions one after another, with no time in between training sessions test Spaced training, with some time in between training sessions test Massed training tends to trigger short term, mid term and even anaesthesia resistant memory Spaced training triggers all types of memory, and is more likely to induce long term memory

15 Learning and memory: how does it work in the brain? Bumblebee brain Section through the brain eye eye The next question: How can insects learn and what brain areas are involved? Three dimensional reconstruction of brain structures